Patients with pneumonia have a fever that is receding, indicating that the condition is progressing toward improvement. A common cause of pneumonia is the invasion of pathogens, such as viruses, bacteria, mycoplasma, chlamydia, and fungi, which cause the mucous membranes of the lungs to become congested and edematous, with inflammatory secretions exuding and producing large amounts of inflammatory factors, and the body temperature will fluctuate and show a gradual increase. At this time, the patient is in the active phase of inflammation. Through anti-inflammatory treatment, the symptoms will be gradually relieved, the inflammation will be controlled, and the body temperature will gradually drop to the normal range, which indicates that the condition is gradually improving. The common clinical treatment is the use of symptomatic anti-inflammatory drugs and the administration of appropriate antipyretic agents.